Summary
Package updates are available for Amazon Linux 2023 that fix the following vulnerabilities: CVE-2026-75803: Check the tag on EVP_Cipher() finalize: Poly1305 and OCB AEADs CVE-2026-63076: Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can contain a parameter of a different type, which is then dereferenced as an invalid pointer. Impact summary: A remote, unauthenticated attacker can crash an application acting as a CMP server that accepts PBM-protected messages, or a CMP client talking to a malicious or intercepted CMP server, resulting in a Denial of Service. CWE: CWE-476: NULL Pointer Dereference Description: When verifying the password-based MAC protection of a CMP message, OpenSSL library reads the protectionAlg algorithm parameter with X509_ALGOR_get0(), which returns both the parameter type and its value pointer. The value is then cast to an ASN1_STRING and treated as the expected PBMParameter after only checking that pointer is not NULL. The parameter type returned by X509_ALGOR_get0() was never consulted. This happens during protection verification, before any MAC is computed, so no knowledge of the PBM shared secret is required; the only precondition is that PBM verification is reachable. On the server side this is reached from OSSL_CMP_SRV_process_request() for any application that stands up a CMP server accepting PBM-protected messages, and on the client side from CMP response validation against a malicious or on-path (MITM) server. The reliable consequence is a denial of service; there is no memory disclosure, no controlled memory write, and no path to code execution. CMP is a specialized feature that an application must explicitly enable. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE. CVE-2026-63075: Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A remote peer that can complete a QUIC handshake can cause connection-scoped memory growth which may lead to Denial of Service through memory exhaustion, especially with sustained traffic or many concurrent QUIC connections. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: When the OpenSSL QUIC stack sends an ACK-only packet, there is no requirement by the QUIC protocol that the peer will acknowledge that ACK-only packet (i.e. it is itself not ack-eliciting). However, the OpenSSL implementation stores the metadata about the ACK frames regardless. In and of itself that's ok, but if a malicious peer establishes a connection, and then drives the connection such that ACK-only packets are forced from the OpenSSL implementation peer (i.e., by sending numerous PING frames), and then withholding any subsequent acks for ack-eliciting data, like legitimate data, said malicious peer can force inappropriate memory growth on the OpenSSL peer, potentially leading to a Denial of Service. The fix is to ensure that we account for the transmission of the ACK-only packet in the packet histories high and low watermark without actually storing the ACK-only packet metadata itself. FIPS impact: no The OpenSSL FIPS module is not affected as the QUIC code is outside the FIPS module boundary. CVE-2026-63074: Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a server reuses an OSSL_CMP_CTX frequently, this cache of extraCerts may grow unboundedly, and a malicious client may flood a CMP server with requests driving this growth. Impact summary: Users utilizing a CMP server that reuses a single OSSL_CMP_CTX for the lifetime of a server process may observe unbounded memory growth in the event a malicious client repeatedly sends requests containing unique extra certificates, which may lead to OOM conditions. CWE: CWE-770: Allocation of Resources Without Limits or Throttling Description: If a remote user sends CMP messages to a server with a list of extraCerts and the message is rejected, the extraCerts from the message remains in the server contexts untrusted certificate stack. This exposes servers with long lived ctx objects to Denial of Service attacks in which an attacker sends messages intending to be rejected with a large list of additional certificates repeatedly, forcing the server to store them indefinitely. The issue was fixed by removing the added extra certs if the message is rejected, using the same method as when the context is configured to not do caching at all. FIPS impact: no As the CMP code lives outside the FIPS module boundary, no FIPS modules are affected by this CVE. CVE-2026-63073: Issue summary: OpenSSL CMP response validation passed an unexpected response sender distinguished name directly as the format string to `ERR_raise_data()`. Impact summary: A malicious or intercepted CMP endpoint can crash a CMP client that enforces an expected sender or uses a pinned server certificate whose subject becomes the default expected sender. CWE: CWE-134 (Use of Externally-Controlled Format String) Description: When validating a received CMP message, ossl_cmp_msg_check_update() converts the peer-supplied sender distinguished name with X509_NAME_oneline() and passes it directly as the format argument to ERR_raise_data(). Percent characters survive the conversion, so a sender DN such as "CN=%s%n" reaches BIO_vsnprintf() as an attacker-controlled format string with no matching variadic arguments. This path is only reached when the caller configures an expected sender or pins a server certificate, which is the normal configuration for a CMP client validating se
Fixed packages 11
| Release | Package | Fixed in |
|---|---|---|
| Amazon Linux · 2023 | openssl | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-debuginfo | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-debugsource | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-devel | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-fips-provider-latest | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-fips-provider-latest-debuginfo | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-libs | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-libs-debuginfo | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-perl | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-snapsafe-libs | 1:3.5.8-1.amzn2023.0.1 |
| Amazon Linux · 2023 | openssl-snapsafe-libs-debuginfo | 1:3.5.8-1.amzn2023.0.1 |
Vulnerabilities 9
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Critical 9.8
Untrusted Sender DN Used as Format String in CMP Response Validation
Issue summary: OpenSSL CMP response validation passed an unexpected response sender distinguished name directly as the format string to `ERR_raise_data()`. Impact summary: A malicious or intercepted CMP endpoint can crash a CMP client that enforces an expecte…
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Critical 9.1
AEAD Forgeries with Empty Ciphertext When Using EVP_Cipher()
Issue summary: ChaCha20-Poly1305 and AES-OCB decryption with an empty ciphertext can report success without verifying the supplied authentication tag when the operation is finalized by calling the EVP_Cipher() function. Impact summary: Applications calling EV…
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High 7.5
RPK Server Signature Algorithm Selection Can Dereference a Missing Certificate
Issue summary: In a server or client configuration with RFC7250 Raw Public Keys (RPKs) enabled, and only the private key (with no associated certificate) configured locally, a NULL pointer dereference may occur when the remote peer solicits raw public keys an…
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High 7.5
QUIC Server May Trigger Double Free When Processing INITIAL Packet
Issue summary: QUIC server may double free QRX (QUIC record layer RX) object when channel creation fails for initial packet. Impact summary: Double free leads to heap corruption, which typically results in termination of QUIC server process, leading to Denial…
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High 7.5
Excessive Memory Use Buffering DTLS Records for a Future Epoch
Issue summary: Receiving a DTLS record for a future epoch while a handshake is in progress causes OpenSSL to buffer far more memory than the record itself requires. Impact summary: A peer can use a small amount of network traffic to make an OpenSSL DTLS endpo…
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High 7.5CVE-2026-63072 Public exploit
Heap Buffer Overflow in CMS Key Unwrapping
Issue summary: OpenSSL CMS decryption sizes the key-unwrap output buffer based on querying the unwrapped key size, but the AES-WRAP-PAD unwrap primitive can write and cleanse more bytes than that query reports, causing an 8-byte out-of-bounds heap write. Impa…
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High 7.5
QUIC ACK-only Packet Retention Can Cause Memory Exhaustion
Issue summary: When OpenSSL processes QUIC traffic from a peer that repeatedly sends ack-eliciting packets while not acknowledging ACK-only responses, the QUIC stack can retain ACK-only packet metadata for the lifetime of the connection. Impact summary: A rem…
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High 7.5
Invalid Pointer Dereference in CMP Server via Crafted protectionAlg
Issue summary: OpenSSL CMP password based protection verification only checks whether the protectionAlg parameter was not NULL and not its ASN.1 type, before treating it as a PBMParameter. A crafted message can contain a parameter of a different type, which i…
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Medium 5.9
CMP Indefinite Cache Growth of ExtraCerts
Issue summary: The OpenSSL Certificate Management Protocol (CMP) caches additional certificates (extraCerts) sent in a CMP message, but never expunges them (for instance if they are invalid). If a server reuses an OSSL_CMP_CTX frequently, this cache of extraC…
References
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-14457.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-18798.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-54874.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-63072.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-63073.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-63074.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-63075.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-63076.html
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web
https://alas.aws.amazon.com/cve/html/CVE-2026-75803.html